Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261204AbUJ3Roi (ORCPT ); Sat, 30 Oct 2004 13:44:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261219AbUJ3Roi (ORCPT ); Sat, 30 Oct 2004 13:44:38 -0400 Received: from mustang.oldcity.dca.net ([216.158.38.3]:10660 "HELO mustang.oldcity.dca.net") by vger.kernel.org with SMTP id S261204AbUJ3Roh (ORCPT ); Sat, 30 Oct 2004 13:44:37 -0400 Subject: Re: [Fwd: Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.4] From: Lee Revell To: Ingo Molnar Cc: Florian Schmidt , Paul Davis , Thomas Gleixner , LKML , mark_h_johnson@raytheon.com, Bill Huey , Adam Heath , Michal Schmidt , Fernando Pablo Lopez-Lezcano , Karsten Wiese , jackit-devel , Rui Nuno Capela In-Reply-To: <20041030111640.GA23493@elte.hu> References: <20041029193303.7d3990b4@mango.fruits.de> <20041029172151.GB16276@elte.hu> <20041029172243.GA19630@elte.hu> <20041029203619.37b54cba@mango.fruits.de> <20041029204220.GA6727@elte.hu> <20041029233117.6d29c383@mango.fruits.de> <20041029212545.GA13199@elte.hu> <20041030003122.03bcf01b@mango.fruits.de> <1099107364.1551.7.camel@krustophenia.net> <1099108122.1551.12.camel@krustophenia.net> <20041030111640.GA23493@elte.hu> Content-Type: text/plain Date: Sat, 30 Oct 2004 13:44:34 -0400 Message-Id: <1099158275.1972.1.camel@krustophenia.net> Mime-Version: 1.0 X-Mailer: Evolution 2.0.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1149 Lines: 26 On Sat, 2004-10-30 at 13:16 +0200, Ingo Molnar wrote: > * Lee Revell wrote: > > > 835 80000000 0.473ms (+0.000ms): finish_task_switch (__schedule) > > 835 80000000 0.474ms (+0.000ms): trace_stop_sched_switched (finish_task_switch) > > 835 80000000 0.474ms (+0.849ms): (835) ((49)) > > 835 80000000 1.324ms (+0.000ms): do_IRQ (finish_task_switch) > > 835 80000000 1.324ms (+0.001ms): do_IRQ ((0)) > > 835 80000000 1.325ms (+0.002ms): mask_and_ack_8259A (__do_IRQ) > > this seems to be very similar to the DMA problems Mark H Johnson had. It > is almost certainly not caused by the kernel. It could in theory be some > SMM overhead, but the bigger likelyhood is disk DMA. > I find this hard to believe - I _never_ saw that problem on this system before. And it works _perfectly_ with T3 - I can run hundreds of millions of process cycles without a single xrun. Lee - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/